validatesessiontag.java

java web模拟的简单的一个网络硬盘

package com.dark.nethd.tags;

import javax.servlet.http.HttpSession;
import javax.servlet.jsp.JspException;
import javax.servlet.jsp.tagext.TagSupport;

import com.dark.nethd.Constants;

public class ValidateSessionTag extends TagSupport {
	private String name = Constants.USER_SESSION_KEY;

	private String page = Constants.LOGON_DEF;

	public int doEndTag() throws JspException {
		boolean valid = false;
		HttpSession session = pageContext.getSession();
		if ((session != null) && (session.getAttribute(name) != null))
			valid = true;

		if (valid)
			return (EVAL_PAGE);
		else {
			try {
				pageContext.forward(page);
			} catch (Exception e) {
				throw new JspException(e.toString());
			}
			return (SKIP_PAGE);
		}
	}

	public int doStartTag() throws JspException {
		return (SKIP_BODY);
	}

	public String getName() {
		return (this.name);
	}

	public String getPage() {
		return (this.page);
	}

	public void release() {
		super.release();
		this.name = Constants.USER_SESSION_KEY;
		this.page = Constants.LOGON_DEF;
	}

	public void setName(String name) {
		this.name = name;
	}

	public void setPage(String page) {
		this.page = page;
	}

}